Prop help please :)

[dezmond]

Hey everyone. Had a blast on the water today with the boat. This was the first time out since we swapped motors and fixed a bunch of stuff up. I did have problems getting it to plane quickly.

Wot, 4000-4500 RPM and took some coaxing to get it on plane (shifting some bodies to the front of the boat). Once on plane I could get the boat going around 25MPH. It took a long time though to get it there . Now my prop has a few small dings and chips and a little bent tips. So I'm thinking that I should be replacing the prop? It a 19p.

Thoughts?

Thanks everyone!

 

[Alumarine]

Did you do a compression test on the "new" motor?
Are you sure the tach is right?
Did you use a GPS to measure speed?
How many bodies are we talking about?

That's not a heavy boat and even with a 19p it should go faster than that and the revs should be higher with that boat/prop.

 

[dezmond]

Went by the tach on the boat. Plan to do compression test. 4 bodies but that would be around 750lbs. When we got back we checked the plugs and they were a little rich so we adjusted and will be back on the water again today. I am thinking my prop may be the right pitch for the boat but the condition of it may be the problem. Some nicks, bent a bit in some areas , etc. I know I have to do a compression test and that will be done tomorrow night. I wanted to get it in the water to make sure everything else was ok.

 

[ziggy]

an 87 120 wot spec is 4200-4600. seems like your kinda in the range. I'd say fix (or replace w/similar 19p prop) the prop and then see where it leads ya. a couple less body's and it might be right there in spec. as for the 25mph. that does seem a bit slow. i''ve no answer for that other than maybe that's all she'll do. reaching wot spec. is where it's at imho.

 

[dezmond]

I think speed is affected from all the weight in the boat. I am sure it will speed up with less weight and a better condition prop.

 

[Islandlaker]

I had the same problem, tried a smaller size prop and it fixed my issue. I know some prop shops will let you buy a prop and keep exchanging it with them until you find the right one. Just don't hit any rocks!

 

[jimmbo]

When you 'swapped' engines', what was in it before and what exactly did you swap in?

 

[dezmond]

It had a Ford 2.3 but no outdrive so I used what I had which was came out of my 18' grew.

 

[Sea Rider]

If engine is in excellent shape, like boating with 4 souls most of the time, you should dial a less prop pitch that achieves full wot rpm for that engine while running with 4 up. When with lesss souls say 2, just throttle less and watch tach no to over rev. Hole shot will be excellent along nice boating throughout the whole throttle range.

Happy Boating

 

[dezmond]

I think I found one..

http://boatpropellers.iboats.com/Me..._031042_Propeller/474/9656/?cart_id=015895223

It is a 17p. That would be better off for hole shot??? Most of the time there will be 4 bodies in the boat and the youngest one does not like to go real fast so I won't really be going WOT very often with him in the boat.. I don't care much for top speed anyways myself as I like to mostly cruise around and have fun with the family. We are never in a hurry to get anywhere

If I picked the wrong one, could you help suggest?

Thanks!!

Dezi

 

[Sea Rider]

Need the wot rpm readings while at full hammer down with 4 souls to check if inside min-max wot rpm range for that engine. Which is the wot range for that 2.3 Ltr engine ? Once propped at max wot range, just throttle at your preffered boating speed, but if in need to go faster and have extended fun engine will rev happily towards its max wot range.

Happy Boating

 

[jimmbo]

It had a Ford 2.3 but no outdrive so I used what I had which was came out of my 18' grew.

What engine was on the outdrive from your 18 ft grew? The boat had a 2.3 and you replaced it with another 2.3? If so was the replacement engine a marine engine or an auto engine from a wrecker?

 

[dezmond]

The Grew had the Mercruiser 120 with MC1 Outdrive ( in my signature)... it was a marine engine.